Introduction: Forensic nurses routinely provide services to sexual assault victims who are uncertain about reporting their assault to police. The purpose of this study was to determine whether assault characteristics are related to the concerns about police reporting expressed by sexual assault victims who have forensic evidence collected but do not report their assault to police at that time. Methods: We analyzed medical records of patients who received services at a hospital-based forensic nursing program between 2010 and 2021. Records were included if a sexual assault evidence kit was collected, the patient declined to report the assault to police, and the patient completed a nonreport sexual assault evidence kit supplement form that included a question asking why they chose not to report the assault (N = 296). We qualitatively analyzed patients' reasons for not reporting the assault and then used two-variable case-ordered matrices and chi-square analyses to explore relationships between reasons for not reporting and assault characteristics. Results: Identified reasons for not reporting included lacking information about the assault, fear of harm/retaliation, and self-blame/minimization. Physical force, drug/alcohol consumption, and victim-offender relationship were related to patients referencing lacking information and fearing harm/retaliation as reasons for not reporting, but not related to the frequency of patients referencing self-blame/minimization. Implications: Results indicate that assault characteristics are related to reasons for not reporting at the time of the medical forensic examination. Being aware of these relationships may help forensic nurses provide patient-centered services and anticipatory guidance. Copyright © 2024 The Authors.